﻿Exercise 
  and 
  Humid 
  Heat 
  upon 
  Pulse 
  Rate, 
  etc. 
  

  

  125 
  

  

  and 
  in 
  all 
  probability 
  the 
  calculated 
  percentages 
  can 
  only 
  be 
  regarded 
  as 
  

   rough 
  approximations. 
  

  

  These 
  results 
  thus 
  differ 
  from 
  those 
  of 
  Hunt, 
  who 
  was 
  unable 
  to 
  detect 
  any 
  

   loss 
  of 
  water 
  from 
  the 
  blood 
  by 
  means 
  of 
  haemoglobin 
  estimation, 
  but 
  bear 
  out 
  

   his 
  contention 
  that 
  the 
  bulk 
  of 
  water 
  in 
  the 
  sweat 
  is 
  derived 
  from 
  the 
  

  

  tissues. 
  As 
  an 
  additional 
  source 
  of 
  water, 
  the 
  intestinal 
  canal 
  must 
  be^kep^7 
  tfl 
  Ini 
  

  

  .(a) 
  An 
  increase 
  in 
  the 
  pulse 
  rate 
  and 
  blood 
  pressure, 
  both 
  of 
  which 
  

  

  rapidly 
  fell 
  to 
  normal 
  after 
  discontinuation 
  of 
  the 
  exercise. 
  

   (b) 
  An 
  increase 
  in 
  the 
  carbon 
  dioxide 
  percentage 
  of 
  the 
  alveolar 
  air. 
  

  

  2. 
  The 
  alveolar 
  air 
  at 
  rest 
  in 
  inhabitants 
  of 
  tropical 
  Queensland 
  showed 
  a 
  

   lower 
  carbon 
  dioxide 
  content 
  than 
  the 
  European 
  average. 
  

  

  3. 
  Prolonged 
  exercise 
  led 
  to 
  a 
  rapid 
  increase 
  in 
  the 
  pulse 
  rate 
  and 
  

   temperature 
  at 
  first, 
  which 
  increase 
  became 
  move 
  gradual 
  afterwards, 
  and 
  in 
  

   the 
  case 
  of 
  blood 
  pressure 
  even 
  fell 
  on 
  occasions 
  below 
  normal, 
  on 
  account 
  of 
  

   the 
  profuse 
  sweating. 
  Prolonged 
  exercise 
  had 
  but 
  little 
  effect 
  on 
  the 
  

   alveolar 
  air. 
  

  

  The 
  body 
  temperature 
  during 
  the 
  exercise 
  continued 
  to 
  rise 
  slowly, 
  but, 
  

   considering 
  the 
  light 
  nature 
  of 
  the 
  exercise, 
  the 
  rise 
  in 
  temperature 
  was 
  

   considerable. 
  

  

  4. 
  A 
  considerable 
  loss 
  of 
  water 
  from 
  the 
  body 
  was 
  observed 
  as 
  the 
  result 
  

   of 
  prolonged 
  exercise. 
  Blood 
  estimations 
  showed 
  that 
  this 
  water 
  was 
  mainly 
  

   derived 
  from 
  other 
  sources 
  in 
  the 
  organism 
  than 
  the 
  blood 
  plasma 
  ; 
  a 
  small 
  

   concentration 
  of 
  the 
  blood 
  plasma, 
  however, 
  had 
  taken 
  place. 
  

  

  5. 
  The 
  hot 
  room 
  experiments 
  gave 
  results 
  similar 
  to 
  those 
  caused 
  by 
  

   prolonged 
  exercise, 
  with 
  this 
  difference, 
  that 
  the 
  pulse 
  rate 
  and 
  body 
  

   temperature 
  rose 
  more 
  gradually 
  at 
  first, 
  but 
  a 
  quicker 
  rise 
  took 
  place 
  

   afterwards. 
  

  

  6. 
  The 
  results 
  point 
  to 
  the 
  fact 
  that 
  both 
  exercise 
  and 
  humid 
  heat 
  play 
  a 
  

   part 
  in 
  producing 
  a 
  rise 
  in 
  blood 
  pressure, 
  pulse 
  rate, 
  and 
  rectal 
  tem- 
  

   perature. 
  The 
  degree 
  of 
  rise, 
  however, 
  is 
  controlled 
  by 
  atmospheric 
  con- 
  

   ditions 
  which 
  influence 
  the 
  rate 
  of 
  cooling 
  of 
  the 
  body. 
  

  

  VOL. 
  XCI. 
  B. 
  L 
  

  

  in 
  mind. 
  

  

  Summary. 
  

  

  1. 
  Vigorous 
  exercise 
  of 
  short 
  duration 
  caused 
  — 
  

  

  